Penetration resistant projectile and cartridge for conventional firearms

ABSTRACT

A projectile is disclosed which can be fired from conventional weapons of 40 caliber or larger. The projectile is made from a uniform material mass which has a coefficient of restitution approaching zero, is non-frangible upon impact, and has a sectional density of less than 0.10 pound per square inch. When propelled by a ballistic charge selected to provide impact energy per unit frontal area no greater than 125 foot pounds per square inch with a minimum of 35 foot pounds kinetic energy per projectile, the projectile will not penetrate human flesh. Unless vital areas are hit, the impact will be non-lethal. To enable a marksman to reduce the risk of hitting vital organs, the projectile can be ricocheted off the ground at a very low reflected angle and consequently strike a standing human below the knees. The impact energy can be controlled by varying the incident angle.

Bite Smith States Patet [1.91

[ Sept. 23, 1975 [75] Inventor: Eugene C. Smith, Los Altos. Hills,

Calif.

[73] Assignee: First Round Research, Inc.,

Sunnyvale, Calif.

22 Filed: Sept. 19,1973

21 Appl.No.: 398,893 A Related U.S. Application Data [63] Continuation-in-part of Ser. No. 176,047, Aug. 30,

1971, abandoned.

3,598,058 8/1971 Smith 102/41 FOREIGN PATENTS OR APPLICATIONS 535,992 2/1922 France 102/927 Primary Examiner-Robert F. Stahl [57] ABSTRACT A projectile is disclosed which can be fired from conventional weapons of 40 caliber or larger. The projectile is made from a uniform material mass which has a coefficient of restitution approaching zero, is nonfrangible upon impact, and has a sectional density of less than 0.10 pound per square inch..When propelled by a ballistic charge selected to provide impact energy per unit frontal area no greater than 125 foot pounds per square inch with a minimum of 35 foot pounds kinetic energy per projectile, the projectile will not penetrate human flesh. Unless vital areas are hit, the impact will be non-lethal. To enable a marksman to reduce the risk of hitting vital organs, the projectile can be ricocheted off the ground at a very low reflected angle and consequently strike a standing human below the knees. The impact energy can be controlled by varying the incident angle.

9 Claims, 3 Drawing Figures US Patent Sept. 23,1975 3,906,859

INVENTOR. EUGENE C. SMITH ZZJWMJMW CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of application Ser. No. 176,047, filed Aug. 30, 1971, abandoned concurrently with the filing of this application.

This invention relates to ammunition for firearms and, more particularly, to cartridges having a projectile which is highly resistant to penetration of flesh upon impact.

The use of firearms by guards and police has great and serious disadvantages. First, conventional firearms are so deadly that persons acting in contravention of the orders of police or guards commonly anticipate such weapons not being used. Moreover, when such weapons are used, their penetration upon impact often causes either serious or mortal injury even if vital organs are not hit and thus raises the question as to whether reasonable force was used.

Some recent attempts have been made to adapt firearms to inflict a less than fatal impact. Commonly, however, such firearms are not conventional; rather they must be specially built to fire specially constructed projectiles. While such weapons can be made, their cost is considerable.

Moreover, while attempts have been made to reduce projectile lethality by ricochet from a flat surface, the penetrating ability of conventional projectiles makes this use of conventional projectiles unacceptably lethal.

Accordingly, it is an object of this invention to disclose the physical properties of a new, and novel penetration resistant projectile which can be fired from conventional weapons, and a preferred example of how this projectile is used in a specific cartridge. A preferred specific construction incorporating the penetration resistant physical properties is disclosed.

An advantage of this invention is that the lethality can be controlled by the shooter. Iflethal damage is desirable, direct fire at the vital areas of a human such as the head, lungs, heart, liver and kidneys will typically cause blunt trauma sufficient to kill However if similar blunt trauma is directed to non-vital parts such as the legs, the possibility of serious damage is remote, and the typical result will be temporary incapacitation due to pain, but with no lasting damage.

A further advantage of this invention is that the projectile can impact surfaces such as fiber glass, sheet metal, or the like without penetration; accordingly, firing of the projectile in a critical environment such as an aircraft will realize a minimum risk of damage to delicate equipment.

A further advantage of this invention is that it can be adapted to conventional cartridges of 40 caliber or larger; thus the purchase of specially adapted or constructed firearms is not required.

A further object of this invention is to disclose a projectile which at virtually all angles of incidence upon a substantially horizontal surface maintains a low ricochet or rebound angle.

An advantage of this low ricochet or rebound angle is that the projectile, when fired at a horizontal surface and rebounding onto a standing human, commonly hits at an elevation less than knee high; impact thus occurs well below the vital organs of a standing human, with consequent low risk of lethal damage,

A further advantage of this invention is that the impact energy of the projectile can be controlled by ricochet off of a flat surface, such as the ground. Generally, it has been found that as the incident angle is increased, the impact energy of the projectile on the target is reduced.

A still further advantage of this invention is that if muzzle energy per unit frontal area is less than 275 foot pounds per square inch and the projectile is ricocheted off the ground approximately half way to the target the combination of energy losses due to air resistance and the ricochet will reduce energy per unit frontal area to the penetration resistant level of foot pounds per square inch at all ranges.

Yet another object of this invention is to disclose a projectile of the type described having a unit length to diameter ratio.

An advantage of one to one length to diameter ratio is that the accuracy of the projectileis optimised; the projectile, when fired through a conventional shotgun is capable of hitting an intended target, and missing and avoiding unintended targets.

A further advantage of this invention is that the charge does not deform on being fired and thus reacts when passing through the atmosphere in a manner similar to conventional projectiles.

Other objects, features and advantages of this invention will become more apparent after referring to the following specification and attached drawing, in which:

FIG. 1 is an exploded assembly view of a shotgun cartridge of this invention, the assembly view showing the wadding projectiles, and propellant charge overlying a conventional shotgun cartridge case and primer;

FIG. 2 shows the assembled cartridge; and

FIG. 3 is a cartoon view of the weapon being used in its preferred manner against a human.

Referring to FIG. 1, an exploded assembly view of a shotgun cartridge is illustrated. A conventional 12 gauge cartridge case and primer A are shown having the propellant charge B and projectiles C immediately prior to loading.

Cartridge case A is typically a cylinder of metal, plastic or cardboard which has at the bottom portion thereof an impact primer. This is completely conventional, and can be purchased from any number of sources. It is preferred that cartridge case A be transparent and distinctly color coded to identify the cartridges of this invention from similar conventional and lethal cartridges.

Propellant charge B is a relatively weak charge of powder. Typically, five grains of conventional smokeless powder sold under the registered trademark BULLSEYE of the Hercules Powder Company is sufficient powder load to discharge two 0.3 ounce projectiles of this invention to appropriate velocities from a 12 gauge shotgun. As is apparent to those skilled in the art, other powders and charge weights can be used.

Typically, charge B is selected to provide each projectile with a muzzle energy per unit frontal area in the range of foot pounds per square inch and no greater than 275 foot pounds per square inch. It should be realized that this energy can be varied by those skilled in the art. This muzzle energy per unit frontal area, however, is preferred.

Overlying the powder load is a cup shaped wad which is typically plastic or cardboard of construction and designed to overlie, protect and shield the shotgun charge B. This closed cylinder or wad 14 serves as the gas obturation during firing, a function well known to those skilled in the art. It also serves to prevent any chemical from leaking out of projectile C and permeating the propellant charge causing it to fire inefficiently.

Projectile C is formed from a uniformly distributed substance which will deform upon impact. Typically, the material is physically plastic and is molded into a cylindrical plug so as to conveniently fit within a shotgun bore. Alternately, the material can be-formed into a sphere and packed in an inert powder which is nonhygroscopic.

Several important observations can be made about the plastic used with this invention. First, it is preferred that the coefficient of restitution or elasticity of the substrate from which the projectile is made be as low as possible. While a coefficient of restitution approaching zero is preferred, it should be realized that some coefficient of restitution can be tolerated. In any event the coefficient of restitution must be below 0.3 for the ricochet effect to be practical. It should be noted that the coefficient of restitution of commercially available lead shot is in the range of 0.5.

Secondly, it is required that the substance selected for the projectile be substantially non-frangible upon impact. It should impact its target as a mass and not break apart or split up. Since in ricochet the projectile may be subjected to impacts on a hard surface at velocities of up to 800 feet per second at incident angles of up to 60, this non-shattering property is critically important. It should be noted that commonly available materialswith very low coefficients of restitution such as clay and putty do not possess this cohesiveness to any useful degree. A minimum non-frangibility enabling-impact upon a hard surface at a-i/elocity up to 400 feet per second at incident angles up to 30 without breaking apart is required.

As a further limitation, the sectional density of the projectile should be less than 0.10 pounds per square inch upon impact since higher sectional densities greatly limit the ability of the projectile to deliver energy without risking penetration.

Moreover, it is preferred that the plastic does not change its shape upon being fired. Thus, during its travel through the atmosphere, it will react as a conventional projectile and will not be subject to variable trajectory due to deformation.

Also, the plastic properties of the projectile must not change due to changes in ambient temperature. It is preferred that the plastic properties remain essentially constant between 125F. and -40F.

In actual practice, it is preferred that the specific gravity of the charge be in the range of less than 3. As distinguished from this, commercially available lead shot has a density in the range of 12.

In the sample ofa 12 gauge cartridge illustrated here, it is preferred that each of the projectiles and 24 be of equal weight and weigh 0.3 ounces each. Weights in a 12 gauge load in the range of 0.5 ounces have been successfully used.

A product which maintains all of the above-described properties is sold under the registered trademark DUX- SEAL by the Johns Mansville Corporation. This material is disclosed as an asbestos base plastic sealing compound commonly used to seal electrical conduits and the like. Duxseal is a mixture of blown castor oil and asbestos fiber in a ratio of 60 to 40 parts. Duxseal has a flow-rate through a inch orifice from a 6 inch diameter cylinder under a pressure of 100 psi at 20C of about 0.1 to 0.5 oz/sec.

Products which find particular use are blown vegetable oils which are polyunsaturated mixed with asbestos fiber to provide a product having the desired flow and restitution properties. The amount of the blown vegetable oil will normally be about 40 to parts by weight with from 60 to 30 parts by weight of asbestos fiber respectively.

Small amounts of other materials may also be included, generally less than 10, usually less than 5, Weight percent of the composition, such as dyes, elastomers, antioxidants, plasticizers and the like.

It should be understood that other material can be empirically located which will maintain the physical properties and parameters herein described. It is the purpose to set forth herein the properties and parameters to guide those who would practice this invention.

It has become apparent that a fibrous filler in combination with a plastic binder is an extremely desirable constituent in enabling the mass to achieve these described properties, especially non-frangibility. Thus, the term plastic as used herein, describes a homogeneous mass capable of continuous and permanent change of shape without breaking apart, whether or not the mass includes a fibrous filler.

It is preferred that the projectile C be encompassed within a protective wrapper. Typically, such wrappers 16 are formed with a circular disc-shaped body having two rectangular pieces of plastic attached thereto. Usually, the disc-shaped portion of the wrapper is placed over one end of the projectile and the two rectangular pieces of plastic used to wrap and encase the sidewalls of the projectile. The remaining circular end of the projectile is typically covered by a cardboard wad.

Referring to FIG. 1, it will be seen that two projectiles C can b e used. Projectile 20, adjacent charge B has its lower end covered by the disc-shaped portion of the wrapper 16 with the two sides covered by the rectangular portions of the wrapper. Overlying projectile 20 there is placed second wadding 22 followed by second projectile 24 and wrapper 26. As can be seen, 26 fits over the lower end of second projectile 24 in the same orientation as 16 and has its two rectangular portions wrapping the charge.

The charge is finally loaded to the shell and held within the shell by a cardboard wad 30 typically of 5/100ths of an inch thickness. As the wadding is well understood in the shotgun art, it will not further be discussed herein.

The cartridge disclosed herein is fired in a conventional manner from shotguns. Typically, the gun is opened, the cartridge inserted, fired and the empty shell is ejected.

It has been found by high speed photography that in flight, the projectile does not deform. Accuracy of the projectile is thus retained.

It will be noted that the invention illustrates two projectiles, each projectile defining a length to diameter ratio of approximately one. It is preferred to have a length to diameter ratio in the range of approximately one-to-one to preserve accuracy. It has been found that if the length-to-diameter ratio is increased to the area of 1.5, considerable accuracy is lost beyond 20 yards.

Referring to the schematic view of FIG. 2, two important features of this invention are illustrated. These features are the property of the projectile C to have a ricochet angle which is small compared to the incident angle and the property of the projectile in dissipating energy in direct proportion to the sine of the angle of incidence of the projectile on a flat surface.

Referring to FIG. 2, a marksman D is shown firing a projectile at a target E here shown as a human. The distance between the marksman D and the target is approximately 30 feet.

First, in firing the projectile directly at vital areas of target E, an impact on the target sufficient to kill is achieved. Actual tests on animals have proven this. Secondly, when the projectile is fired at the ground, a ricochet impact on the target will occur. In the case of a man of normal size, the impact after ricochet will be at the knees or lower. This will occur if the projectile is ricocheted at a point half-way to the target or beyond. Empirically, it has been discovered that although considerable variation is experienced with respect to the angle of incidence (a), the angle of ricochet (B) reflection remains small, typically related by Tan a/Tan ,8 10.

Additionally, it has been found that greater angles of incidence dissipate considerably greater amounts of energy. Thus, it can be seen that the marksman D can readily control the amount of energy which projectile C delivers to target E. By aiming at a point closer to the shooter the angle of incidence is increased and a considerable amount of energy will be dissipated and thus the impact at the target will be reduced. Conversely, by firing at a low angle of incidence, most of the energy will be conserved and relatively high energy impact at the target will occur.

It is anticipated that this invention will be most useful in riot situations. By firing at a flat surface such as a street or sidewalk, lower than knee high impact on rioters will be achieved. The incidence of penetration of flesh will be minimal.

Moreover, since the impact will be below the knees, vital organs will not be affected.

It should be understood that this invention is not held out as being a non-fatal weapon. The projectile of this invention when used at close ranges for direct impact on vital areas ofa human target will kill. This projectile, however, when used carefully in a riot situation can be used to minimize the risk of mortal wounding far below that risk now realized by conventional weapons.

It should be apparent that many modifications could be made to the above invention.

Likewise, other modifications to the size of the charge, size of the weapon and the like can be made without departing from the spirit and scope of this invention.

What is claimed is:

l. A cartridge for a weapon having a firing chamber and muzzle comprising: at least one plastic projectile of preselected weight having a coefficient of restitution less than 0.3, having a sectional density of less than 0.10 pounds per square inch, and having non-frangibility enabling impact of a hard surface at a velocity up to 400 feet per second at incident angles of up to 30 with out breaking apart; a propellant charge for said projectile selected with respect to said preselected weight to provide energy per unit frontal area at said weapon muzzle no greater than 275 foot pounds per square inch and a minimum kinetic energy per projectile at said weapon muzzle of at least 35 foot pounds, wherein said plastic projectile has at least about 90 weight percent of a combination of blown vegetable oil in from 40 to parts by weight and respectively 60 to 30 parts by weight of asbestos fiber.

2. The invention of claim 1 and wherein said projectile comprises a blown castor oil as a binder.

3. The invention of claim 1 and wherein a plurality of projectiles are fired by said propellant charge, each projectile being cylindrical in shape, aligned in end-toend relation and having a thickness diameter ratio in the range of 1.

4. The invention of claim 1 and wherein the plastic properties of said projectile remain substantially unchanged in the range between 125 Fahrenheit and 40 Fahrenheit.

5. In a weapon combination including a gun bore closed at one end for containing the combustion of a propellant charge and open at the other end for propelling a projectile, a charge placed in said bore adjacent the closed end thereof and a projectile located within said bore between the open end thereof and said propellant charge, the improvement in said projectile and said propellant charge comprising: a projectile of preselected weight made from a plastic material mass having at least weight percent of a combination having 40 to 70 parts by weight of a blown vegetable oil and respectively 60 to 30 parts by weight of asbestos fiber and having a coefficient of restitution less than 0.3, having a sectional density less than 0.10 pounds per square inch, and having non-frangibility enabling impact upon a hard surface at a velocity up to 400 feet per second at incident angles up to 30without breaking apart, a propellant charge selected with respect to the preselected weight of said projectile to provide energy to said projectile per unit frontal area no greater than 275 foot pounds per square inch with a minimum kinetic energy per projectile at the muzzle of said bore at 35 foot pounds.

6. The invention of claim 5 and wherein said projectile comprises a blown castor oil as a binder.

7. The invention of claim 5 and wherein a plurality of projectiles are fired from said weapon.

8. The invention of claim 5 and wherein the length to the diameter ratio of each said projectile is l.

9. The invention of claim 5 and wherein said projectile comprises two discrete portions of material placed in end-to-end relation. 

1. A CARTRIDGE FOR A WEAPON HAVING A FIRING CHAMBER AND MUZZLE COMPRISING: AT LEAST ONE PLASTIC PROJECTILE OF PRESELECTED WEIGHT HAVING A COEFFICIENT OF RESTITUTION LESS THAN 0.3, HAVING A SECTIONAL DENSITY OF LESS THAN 0.10 POUNDS PER SQUARE INCH, AND HAVING NON-FRANGIBILITY ENABLING IMPACT OF HARD SURFACE AT A VELOCITY UP TO 400 FEET PER SECOND AT INCIDENT ANGLES OF UP TO 30* WITHOUT BREAKING APART, A PROPELLANT CHARGE FOR SAID PROJECTILE SELECTED WITH RESPECT TO SAID PRESELECTED WEIGHT TO PROVIDE ENERGY PER UNIT FRONTAL AREA AT SAID WEAPON MUZZLE NO GRATER THAN 275 FOOT POUNDS PER SQUARE INCH AND MINIMUM KINETIC ENERGY PER PROJECTILE AT SAID WEAPON MUZZLE OF AT LEAST 35 FOOT POUNDS, WHEREIN SAID PLASTIC PROJECTILE HAS AT LEAST ABOUT 90 WEIGHT PERCENT OF A COMBINATION OF BLOWN VEGETABLE OIL IN FROM 40 TO 70 PARTS BY WEIGHT AND RESPECTIVELY 60 TO 30 PARTS BY WEIGHT OF ASBESTOS FIBERS.
 2. The invention of claim 1 and wherein said projectile comprises a blown castor oil as a binder.
 3. The invention of claim 1 and wherein a plurality of projectiles are fired by said propellant charge, each projectile being cylindrical in shape, aligned in end-to-end relation and having a thickness diameter ratio in the range of
 1. 4. The invention of claim 1 and wherein the plastic properties of said projectile remain substantially unchanged in the range between 125* Fahrenheit and -40* Fahrenheit.
 5. In a weapon combination including a gun bore closed at one end for containing the combustion of a propellant charge and open at the other end for propelling a projectile, a charge placed in said bore adjacent the closed end thereof and a projectile located within said bore between the open end thereof and said propellant charge, the improvement in said projectile and said propellant charge comprising: a projectile of preselected weight made from a plastic material mass having at least 90 weight percent of a combination having 40 to 70 parts by weight of a blown vegetable oil and respectively 60 to 30 parts by weight of asbestos fiber and having a coefficient of restitution less than 0.3, having a sectional density less than 0.10 pounds per square inch, and having non-frangibility enabling impact upon a hard surface at a velocity up to 400 feet per second at incident angles up to 30*without breaking apart, a propellant charge selected with respect to the preselected weight of said projectile to provide energy to said projectile per unit frontal area no greater than 275 foot pounds per square inch with a minimum kinetic energy per projectile at the muzzle of said bore at 35 foot pounds.
 6. The invention of claim 5 and wherein said projectile comprises a blown castor oil as a binder.
 7. The invention of claim 5 and wherein a plurality of projectiles are fired from said weapon.
 8. The invention of claim 5 and wherein the length to the diameter ratio of each said projectile is
 1. 9. The invention of claim 5 and wherein said projectile comprises two discrete portions of material placed in end-to-end relation. 